The present invention relates to methods and apparatus for transferring data within a multi-processing system.
In recent years, there has been an insatiable desire for faster computer processing data throughputs because cutting-edge computer applications involve real-time, multimedia functionality. Graphics applications are among those that place the highest demands on a processing system because they require such vast numbers of data accesses, data computations, and data manipulations in relatively short periods of time to achieve desirable visual results. These applications require extremely fast processing speeds, such as many thousands of megabits of data per second. While some processing systems employ a single processor to achieve fast processing speeds, others are implemented utilizing multi-processor architectures. In multi-processor systems, a plurality of sub-processors can operate in parallel (or at least in concert) to achieve desired processing results.
In some multi-processing systems, each processor may employ a relatively small local memory in which to execute program code (as opposed to a larger random access memory, RAM). The larger RAM (main or system memory) may be used for bulk storage. The processors may also employ direct memory access (DMA) technology to transfer data from the main memory to the respective local memories.
In a multi-processor system, it may be desirable for the plurality of processors to have access to data in a very wide range of space, such as in other multi-processor systems that are located remotely but accessible over a network. As the latency associated with data transfers between remotely located system may be unpredictable, prior art techniques for managing memory spaces in multi-processor systems are not satisfactory in this regard.